:root {
  --bg: #f5f7fb;
  --card: rgba(255,255,255,.86);
  --text: #172033;
  --muted: #697386;
  --line: rgba(23,32,51,.09);
  --accent: #3478f6;
  --radius: 22px;
  --shadow: 0 14px 40px rgba(25, 42, 70, .08);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(52,120,246,.14), transparent 32rem),
    radial-gradient(circle at top right, rgba(130,87,229,.10), transparent 30rem),
    var(--bg);
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
.container { width: min(1080px, calc(100% - 32px)); margin: 0 auto; }
header {
  position: sticky; top: 0; z-index: 10;
  backdrop-filter: blur(18px);
  background: rgba(245,247,251,.74);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; min-height: 64px; }
.brand { font-weight: 750; letter-spacing: -.02em; }
nav { display: flex; gap: 22px; color: var(--muted); font-size: 15px; }
nav a:hover { color: var(--text); }
.hero { padding: 96px 0 54px; }
.eyebrow { color: var(--accent); font-weight: 700; font-size: 14px; }
h1 { margin: 10px 0 18px; font-size: clamp(40px, 7vw, 72px); line-height: 1.05; letter-spacing: -.05em; }
h2 { margin-top: 0; letter-spacing: -.025em; }
.lead { max-width: 720px; color: var(--muted); font-size: 19px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.button {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 18px; border-radius: 14px; font-weight: 650;
  border: 1px solid var(--line); background: rgba(255,255,255,.72);
}
.button.primary { background: var(--accent); color: white; border-color: transparent; }
.grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; padding: 20px 0 76px; }
.card {
  padding: 24px; border-radius: var(--radius); background: var(--card);
  border: 1px solid rgba(255,255,255,.9); box-shadow: var(--shadow);
}
.card p { color: var(--muted); margin-bottom: 0; }
.page { padding: 72px 0; min-height: calc(100vh - 130px); }
.list { display: grid; gap: 14px; margin-top: 30px; }
.item {
  display: block; padding: 20px 22px; border-radius: 18px;
  background: var(--card); border: 1px solid var(--line);
}
.item:hover { transform: translateY(-1px); box-shadow: var(--shadow); }
.item small { color: var(--muted); }
textarea {
  width: 100%; min-height: 260px; resize: vertical; padding: 16px;
  border-radius: 16px; border: 1px solid var(--line); background: white;
  color: var(--text); font: 14px/1.55 ui-monospace, SFMono-Regular, Menlo, monospace;
}
.tool-actions { display: flex; flex-wrap: wrap; gap: 10px; margin: 14px 0; }
button {
  cursor: pointer; padding: 11px 16px; border: 0; border-radius: 12px;
  background: var(--accent); color: white; font-weight: 650;
}
button.secondary { background: #e9eef8; color: var(--text); }
.status { min-height: 24px; color: var(--muted); font-size: 14px; }
footer { padding: 28px 0 44px; color: var(--muted); border-top: 1px solid var(--line); }
@media (max-width: 760px) {
  nav { gap: 14px; font-size: 14px; }
  .hero { padding-top: 64px; }
  .grid { grid-template-columns: 1fr; }
}